arm64: defconfig: Enable TMPFS Posix ACL

The lack of TMPFS Posix ACL prevents the upstream defconfig from booting
e.g. Ubuntu, so enable this.

Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

arch/arm64/configs/defconfig

@@ -1075,6 +1075,7 @@ CONFIG_FUSE_FS=m
 CONFIG_CUSE=m
 CONFIG_OVERLAY_FS=m
 CONFIG_VFAT_FS=y
+CONFIG_TMPFS_POSIX_ACL=y
 CONFIG_HUGETLBFS=y
 CONFIG_CONFIGFS_FS=y
 CONFIG_EFIVAR_FS=y